It possesses the characters of the sandy group and within the species sandy group, it can be diagnosed by the following characters: elongate naked area at tip of snout reaching the most anterior pore of the infraorbital sensory canal (vs. oval naked area at tip of snout, not reaching the most anterior pore of the infraorbital sensory canal in Rineloricaria quadrensis, Rineloricaria misionera, and Rineloricaria strigilata b); plain, light brown background color (vs. with numerous dark and vermiculated spots on a light brown background in Rineloricaria strigilata); dorsal unbranched caudal-fin ray not prolonged (vs. dorsal unbranched caudal-fin ray produced as a short filament in Rineloricaria catamarcencis); usually three series of plates between the lateral abdominal plates (vs. four of five series in Rineloricaria catamarcensis and Rineloricaria felipponei); deeper body, depth at anal-fin origin 7.9-9.4% SL (vs. 6.0-7.4% SL in Rineloricaria longicauda in specimens above 10 cm SL); and comparatively larger plates covering the pectoral girdle, usually 5-6 plates transversally and usually three series of plates between the lateral abdominal plates (vs. many small plates covering the pectoral girdle, usually over 15 platelets, and four of five series of plates between the lateral abdominal plates in Rineloricaria pareiacantha and Rineloricaria thrissoceps (Ref. 75788).